In the assembly of race cars with rear wheel drive with a differential gear in the rear and engine and transmission in the front of the race car, it is necessary to align the axis of the output shaft of the transmission with the input shaft of the differential gear to avoid vibration and to improve performance. Current practice for aligning the axis of the transmission output shaft with the input shaft of the differential gear has been by trial and error and through observations. A need exists for an improved alignment system to facilitate proper positioning of the differential input shaft relative to the transmission when a race car is being assembled.